An imaging element for an electronic endoscope is disclosed. The electronic endoscope has an elongated tubular main body. At the tip end portion of the main body, there are provided an optical imaging system comprising a convex lens, a concave lens and an optical low-pass filter, a CMOS type imaging element having a CMOS sensor, and a pair of light distribution lenses. The imaging element includes the CMOS sensor, a signal processing circuit for processing a signal outputted from the CMOS sensor, and a signal control circuit for timing control for extracting a signal from the CMOS sensor. In this imaging element, the signal processing circuit and the signal control circuit are arranged along the periphery of the light-receiving surface of the CMOS sensor so that a center of the base of the sensor on the light-receiving surface is substantially aligned with a center of an effective imaging region of the image sensor.